(Meredith) – A teacher accidentally fired a pistol inside a California classroom while lecturing about public safety and injured three students, according to police.

Dennis Alexander was pointing the gun at the ceiling when he inadvertently fired it Tuesday at Seaside High School, said Abdul Pridgen, the city's police chief.

Bullet fragments ricocheted off the ceiling and hit a 17-year-old student in the neck, Pridgen said. Shortly after the incident, class resumed as usual.

The teen’s father, Fermin Gonzales, said he rushed his son to the hospital after the 17-year-old returned from school with blood on his shirt and a neck injury.

“He’s shaken up, but he’s going to be OK,” Gonzales told KSBW. “I’m just pretty upset that no one told us anything and we had to call the police ourselves to report it.”

Two other students were also injured by debris, but police said all of their injuries are minor.

Alexander also serves as a reserve officer for Sand City police and is a Seaside city councilman.

The police department and school district placed Alexander on administrative leave while investigating whether he was legally allowed to have a gun on campus.

"I think a lot of questions on parents' minds are, why a teacher would be pointing a loaded firearm at the ceiling in front of students," Superintendent PK Diffenbaugh told KSBW. "Clearly in this incident protocols were not followed."

Guns and other weapons are prohibited on school grounds, though there are exceptions involving law enforcement.